Operating System (OS) for built-in apparatuses such as consumer products is now shifting from conventional real-time Operating Systems (RTOS) to general-purpose Operating Systems such as Linux™ and Symbian™. However, application programs have a program structure that depends on hardware and an OS. Therefore, in order to run an application program for the RTOS on a different OS, it is necessary to make some changes to the application in accordance with the different OS. Due to the shifting mentioned above, there is a problem that a heavy workload is required for porting the applications to the general-purpose OS.
As a solution for such a problem, there is a possibility that use of virtualization technique allows different OSs to operate on the same hardware without any changes to the existing OSs and application programs, and lightens the workload. Note that the virtualization technique is explained in detail on pages 38-45 of the Non-patent Document shown below.
For application of such a virtualization technique, in some cases, two application programs that run on different OSs have to share data and cooperate with each other. The Patent Document 1 shown below discloses a technique to handle this situation. According to the Patent Document 1, an inter-OS shared memory and an inter-OS notification function are included in an inter-OS control function for controlling operations of a plurality of OSs, and when one of the OSs changes the shared data, it notifies the other OSs about the change, using the inter-OS notification function.
FIG. 27 shows the shared-date change notification function disclosed in the Patent Document 1 as a conventional art. According to FIG. 7, a task C 2202 running on a first OS and a task D 2203 running on a second OS share data, using an inter-OS shared memory. Note that the inter-OS shared memory is a memory region obtained from a memory space shared between the first OS and the second OS. Firstly, the task C 2202 obtains the inter-OS shared memory. After that, when registering data with the obtained shared memory or changing the data, the inter-OS notification function notifies the task D 2203 about the registration or the change.    Patent Document 1: Japanese Laid-open Patent Application Publication No. 2001-243080    Patent Document 2: Japanese Laid-open Patent Application Publication No. 2000-347772    Non-patent Document 1: UNIX magazine, 2007-January issue, ASCII corp. (2007)